Optomotor behaviour in Xenopus laevis tadpoles as a measure of the effect of gravity on visual and vestibular neural integration.

The ability of aquatic vertebrates to maintain their position requires integration of visual and vestibular sensory information. To understand better how aquatic animals integrate such information, we measured the optomotor behaviour of Xenopus laevis tadpoles raised in growth chambers in microgravity (< 10(-3)g), normal gravity (1 g), hypergravity (3 g) and on a slowly rotating clinostat (simulated microgravity). The goal of this research was to determine how development in an altered gravitational force field affects the visual- and vestibular-dependent behaviour of tadpoles. This research represents the first time that the optomotor behaviour of an organism raised from fertilization in microgravity has been tested. Significant differences were observed in the optomotor behaviour among the four gravity treatments. When first exposed to normal gravity, the microgravity-raised tadpoles exhibited the strongest (or most positive) optomotor behaviour, while the 3 g centrifuge tadpoles showed no optomotor response. Some abnormal behaviours (such as erratic swimming, lying motionless and abnormal swimming posture) were observed in the tadpoles raised in altered gravity on the initial day of testing. One day later, the tadpoles raised in hypergravity did not differ significantly in their optomotor behaviour from control tadpoles raised in normal gravity. However, tadpoles raised in microgravity still displayed an exaggerated optomotor response. One week after the tadpoles had been introduced to normal gravity, there was no longer a significant difference in optomotor behaviour among the different gravity treatments. This convergence of optomotor behaviour by tadpoles from the different treatment reflects the acclimation of their vestibular systems to normal gravity.

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The large invasive population of Xenopus laevis in Sicily, Italy

Amphibia-Reptilia ◽

10.1163/156853808785112075 ◽

2008 ◽

Vol 29 (3) ◽

pp. 405-412 ◽

Cited By ~ 26

Author(s):

Gabriele Giacalone ◽

Mario Lo Valvo ◽

Francesco Paolo Faraone ◽

Francesco Lillo

Keyword(s):

Xenopus Laevis ◽

Amphibian Declines ◽

African Clawed Frog ◽

Significant Difference ◽

Planktonic Crustaceans ◽

Geographic Regions ◽

First Time ◽

Clawed Frog ◽

Sicilian Population ◽

Strong Ability

Abstract The worldwide spread of invasive species is considered to be one of the main causes of global amphibian declines and the loss of biodiversity in general. The African Clawed Frog, Xenopus laevis, shows a strong ability to establish populations and invade various geographic regions. In 2004 X. laevis was found in Sicily for the first time. The Sicilian population is probably the largest in Europe with a range of about 225 km2 in an area characterized by numerous agricultural ponds. This high density of ponds has potentially facilitated the dispersal of X. laevis. The frogs can move far from rivers or watercourses by utilizing the ponds as suitable "islands". The analysis of their diet shows that the aquatic larvae of nektonic insects comprise the major portion in terms of mass while small planktonic crustaceans are the most numerous component. There is a significant difference between the diet of adults and juveniles.

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Role of MicroRNA Genes miR-1000 and miR-375 in Forming Olfactory Conditional Memory in Drosophila melanogaster

MicroRNA ◽

10.2174/2211536609666200204113403 ◽

2020 ◽

Vol 09 ◽

Author(s):

Sadniman Rahman ◽

Chaity Modak ◽

Mousumi Akter ◽

Mohammad Shamimul Alam

Keyword(s):

Learning And Memory ◽

Short Term Memory ◽

Memory Loss ◽

Memory Formation ◽

Neural Integration ◽

Significant Difference ◽

Locomotion Speed ◽

Microrna Genes ◽

With Memory

Background: Learning and memory is basic aspects in neurogenetics as most of the neurological disorders start with dementia or memory loss. Several genes associated with memory formation have been discovered. MicroRNA genes miR-1000 and miR-375 were reported to be associated with neural integration and glucose homeostasis in some insects and vertebrates. However, neuronal function of these genes is yet to be established in D. melanogaster. Objective: Possible role of miR-1000 and miR-375 in learning and memory formation in this fly has been explored in the present study. Methods: Both appetitive and aversive olfactory conditional learning were tested in the miR-1000 and miR-375 knockout (KO) strains and compared with wild one. Five days old third instar larvae were trained by allowing them to be associated with an odor with reward (fructose) or punishment (salt). Then, the larvae were tested to calculate their preferences to the odor trained with. Learning index (LI) values and larval locomotion speed were calculated for all strains. Results: No significant difference was observed for larval locomotion speed in mutant strains. Knockout strain of miR-1000 showed significant deficiency in both appetitive and aversive memory formation whereas miR-375 KO strain showed a significantly lower response only in appetitive one. Conclusion: The results of the present study indicate important role played by these two genes in forming short-term memory in D. melanogaster.

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Molecular Detection and Phylogeny of Anaplasmaphagocytophilum and Related Variants in Small Ruminants from Turkey

Animals ◽

10.3390/ani11030814 ◽

2021 ◽

Vol 11 (3) ◽

pp. 814

Author(s):

Münir Aktaş ◽

Sezayi Özübek ◽

Mehmet Can Uluçeşme

Keyword(s):

16S Rrna ◽

Small Ruminants ◽

Rrna Gene ◽

Infection Rates ◽

Sheep And Goats ◽

Significant Difference ◽

Pcr Rflp ◽

First Time ◽

Japan And China ◽

Apparently Healthy

Anaplasma phagocytophilum causes tick-borne fever in small ruminants. Recently, novel Anaplasma variants related to A. phagocytophilum have been reported in ruminants from Tunisia, Italy, South Korea, Japan, and China. Based on 16S rRNA and groEL genes and sequencing, we screened the frequency of A. phagocytophilum and related variants in 433 apparently healthy small ruminants in Turkey. Anaplasma spp. overall infection rates were 27.9% (121/433 analyzed samples). The frequency of A. phagocytophilum and A. phagocytophilum-like 1 infections was 1.4% and 26.5%, respectively. No A. phagocytophilum-like 2 was detected in the tested animals. The prevalence of Anaplasma spp. was comparable in species, and no significant difference was detected between sheep and goats, whereas the prevalence significantly increased with tick infestation. Sequencing confirmed PCR-RFLP data and showed the presence of A. phagocytophilum and A. phagocytophilum-like-1 variant in the sampled animals. Phylogeny-based on 16S rRNA gene revealed the A. phagocytophilum-like 1 in a separate clade together with the previous isolates detected in small ruminants and ticks. In this work, A. phagocytophilum-like 1 has been detected for the first time in sheep and goats from Turkey. This finding revealed that the variant should be considered in the diagnosis of caprine and ovine anaplasmosis.

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Patients Who Attend Alone at a First Memory Consultation: Are They a Specific Population,or Is It an Instance of Confounding Bias?

European Neurology ◽

10.1159/000500483 ◽

2019 ◽

Vol 81 (1-2) ◽

pp. 81-86

Author(s):

Pierre Koskas ◽

Mouna Romdhani ◽

Olivier Drunat

Keyword(s):

Selection Bias ◽

Confounding Bias ◽

Significant Difference ◽

Comparison Groups ◽

Methodological Problems ◽

Group 2 ◽

The Impact ◽

First Time ◽

State Examination ◽

Group 1

As commonly happens in epidemiological research, none of the reported studies were totally free of methodological problems. Studies have considered the influence of social relationships on dementia, but the mechanisms underlying these associations are not perfectly understood. We look at the possible impact of selection bias. For their first memory consultation, patients may come alone or accompanied by a relative. Our objective is to better understand the impact of this factor by retrospective follow-up of geriatric memory outpatients over several years. All patients over 70 who were referred to Bretonneau Memory Clinic for the first time, between January 2006 and 2018, were included in the study. The patients who came alone formed group 1, the others, whatever type of relative accompanied them, formed group 2. We compared the Mini-Mental State Examination (MMSE) scores of patients; and for all patients who came twice for consultation with at least a 60-day interval, we compared their first MMSE with the MMSE performed at the second consultation. In total, 2,935 patients were included, aged 79.7 ± 8.4 years. Six hundred and twenty-five formed group 1 and 2,310 group 2. We found a significant difference in MMSE scores between the 2 groups of patients; and upon second consultation in group 2, but that difference was minor in group 1. Our finding of a possible confounding factor underlines the complexity of choosing comparison groups in order to minimize selection bias while maintaining clinical relevance.

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Quality of life in adolescents and young adults with CHD is not reduced: a systematic review and meta-analysis

Cardiology in the Young ◽

10.1017/s104795111500181x ◽

2015 ◽

Vol 26 (3) ◽

pp. 415-425 ◽

Cited By ~ 12

Author(s):

Morten Schrøder ◽

Kirsten A. Boisen ◽

Jesper Reimers ◽

Grete Teilmann ◽

Jesper Brok

Keyword(s):

Quality Of Life ◽

Systematic Review ◽

Young Adults ◽

Meta Analysis ◽

Adolescents And Young Adults ◽

Analysis Model ◽

Significant Difference ◽

Newcastle Ottawa Scale ◽

First Time

AbstractPurposeWe performed a systematic review and meta-analysis of observational studies assessing quality of life in adolescents and young adults born with CHD compared with age-matched controls.MethodsWe carried out a systematic search of the literature published in Medline, Embase, PsychINFO, and the Cochrane Library’s Database (1990–2013); two authors independently extracted data from the included studies. We used the Newcastle–Ottawa scale for quality assessment of studies. A random effects meta-analysis model was used. Heterogeneity was assessed using the I2-test.ResultsWe included 18 studies with 1786 patients. The studies were of acceptable-to-good quality. The meta-analysis of six studies on quality of life showed no significant difference – mean difference: −1.31; 95% confidence intervals: −6.51 to +3.89, I2=90.9% – between adolescents and young adults with CHD and controls. Similar results were found in 10 studies not eligible for the meta-analysis. In subdomains, it seems that patients had reduced physical quality of life; however, social functioning was comparable or better compared with controls.ConclusionFor the first time in a meta-analysis, we have shown that quality of life in adolescents and young adults with CHD is not reduced when compared with age-matched controls.

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The stress hyperglycaemia ratio is associated with left ventricular remodelling after first acute ST-segment elevation myocardial infarction

BMC Cardiovascular Disorders ◽

10.1186/s12872-021-01889-8 ◽

2021 ◽

Vol 21 (1) ◽

Author(s):

Shuai Meng ◽

Yong Zhu ◽

Kesen Liu ◽

Ruofei Jia ◽

Jing Nan ◽

...

Keyword(s):

Myocardial Infarction ◽

Left Ventricular ◽

Left Ventricular Ejection ◽

Ventricular Ejection Fraction ◽

St Segment Elevation ◽

Segment Elevation Myocardial Infarction ◽

Stress Hyperglycaemia ◽

St Segment ◽

Significant Difference ◽

First Time

Abstract Background Left ventricular negative remodelling after ST-segment elevation myocardial infarction (STEMI) is considered as the major cause for the poor prognosis. But the predisposing factors and potential mechanisms of left ventricular negative remodelling after STEMI remain not fully understood. The present research mainly assessed the association between the stress hyperglycaemia ratio (SHR) and left ventricular negative remodelling. Methods We recruited 127 first-time, anterior, and acute STEMI patients in the present study. All enrolled patients were divided into 2 subgroups equally according to the median value of SHR level (1.191). Echocardiography was conducted within 24 h after admission and 6 months post-STEMI to measure left ventricular ejection fraction (LVEF), left ventricular end-diastolic diameter (LVEDD), and left ventricular end-systolic diameter (LVESD). Changes in echocardiography parameters (δLVEF, δLVEDD, δLVESD) were calculated as LVEF, LVEDD, and LVESD at 6 months after infarction minus baseline LVEF, LVEDD and LVESD, respectively. Results In the present study, the mean SHR was 1.22 ± 0.25 and there was significant difference in SHR between the 2 subgroups (1.05 (0.95, 1.11) vs 1.39 (1.28, 1.50), p < 0.0001). The global LVEF at 6 months post-STEMI was significantly higher in the low SHR group than the high SHR group (59.37 ± 7.33 vs 54.03 ± 9.64, p = 0.001). Additionally, the global LVEDD (49.84 ± 5.10 vs 51.81 ± 5.60, p = 0.040) and LVESD (33.27 ± 5.03 vs 35.38 ± 6.05, p = 0.035) at 6 months after STEMI were lower in the low SHR group. Most importantly, after adjusting through multivariable linear regression analysis, SHR remained associated with δLVEF (beta = −9.825, 95% CI −15.168 to −4.481, p < 0.0001), δLVEDD (beta = 4.879, 95% CI 1.725 to 8.069, p = 0.003), and δLVESD (beta = 5.079, 95% CI 1.421 to 8.738, p = 0.007). Conclusions In the present research, we demonstrated for the first time that SHR is significantly correlated with left ventricular negative remodelling after STEMI.

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BLIND MEXICAN CAVE FISH (ASTYANAX HUBBSI) RESPOND TO MOVING VISUAL STIMULI

Journal of Experimental Biology ◽

10.1242/jeb.188.1.89 ◽

1994 ◽

Vol 188 (1) ◽

pp. 89-101 ◽

Cited By ~ 1

Author(s):

T Teyke ◽

S Schaerer

Keyword(s):

Visual Stimulus ◽

Swimming Velocity ◽

Environmental Cues ◽

Cave Fish ◽

Optomotor Response ◽

Aquarium Fish ◽

Modified Theory ◽

Test Aquarium ◽

Optomotor Behaviour

In apparatus for measuring optomotor behaviour, blind Mexican cave fish, Astyanax hubbsi, increase their swimming velocity upon rotation of a striped cylinder, i.e. in response to a solely visual stimulus. The fish follow the movements of the stripes at (i) rotation velocities between 60 degrees s-1 and 80 degrees s-1, (ii) light intensities of less than 20 lx and, (iii) stimulus widths subtending an angle of less than 1 °. Extirpation of the vestigial eye structures does not affect the response to the moving visual stimulus, which indicates that the response is mediated by extra-ocular photoreceptors. An optomotor response can be reliably evoked in a round test aquarium. Fish do not respond when the test aquarium contains environmental cues, such as bars on the wall or when a section of the round aquarium is divided off. This indicates that the fish obtain information about their environment from different sensory sources and that the visual stimulus is effective only when no other means of orientation are available. We suggest a modified theory of the optomotor response, which emphasizes the crucial role of the environment in eliciting the response and which permits behaviours more complex than just following the stimulus.

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Comparing Executive Function of Normal Children with ADHD Children

International Journal of Psychological Studies ◽

10.5539/ijps.v8n3p11 ◽

2016 ◽

Vol 8 (3) ◽

pp. 11

Author(s):

Fereshteh Heydari ◽

Shohreh Farahani

Keyword(s):

Executive Function ◽

Cognitive Deficits ◽

Measurement Tool ◽

Normal Male ◽

Normal Children ◽

Age And Gender ◽

Significant Difference ◽

Adhd Children ◽

And Gender ◽

First Time

<p>This study was conducted to compare with the executive function of ADHD versus normal male and female children. To obtain this objective, 30 ADHD children referring a private psychological center for the first time who had taken no medication for this disorder, and 30 normal children from one of the schools of District 14 in Tehran were selected randomly who were of the same age and gender of ADHD children. Wisconsin test was used as a measurement tool. Results showed that there is a significant difference between the average scores of the executive function of normal and ADHD children as well as average scores of the executive function of normal boys and ADHD children at the 0.01 level. In addition, there was a significant difference between the average scores of the executive function of normal girls and ADHD girls at the 0.05 level according to which null hypothesis is rejected. Therefore, ADHD children are of lower executive and cognitive function compared to normal children and have extensive cognitive deficits. Therefore, they require medications along with special training and rehabilitation.</p>

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Virological and Epidemiological Features of Norovirus Infections in Brazil, 2017–2018

Viruses ◽

10.3390/v13091724 ◽

2021 ◽

Vol 13 (9) ◽

pp. 1724

Author(s):

Sylvia Kahwage Sarmento ◽

Juliana da Silva Ribeiro de Andrade ◽

Marize Pereira Miagostovich ◽

Tulio Machado Fumian

Keyword(s):

National Level ◽

Age Groups ◽

Median Viral Load ◽

Molecular Surveillance ◽

Predominant Genotype ◽

Significant Difference ◽

Surveillance Programs ◽

Partial Rdrp ◽

Stool Samples ◽

First Time

Noroviruses are considered an important cause of acute gastroenteritis (AGE) across all age groups. Here, we investigated the incidence of norovirus, genotypes circulation, and norovirus shedding in AGE stool samples from outpatients in Brazil. During a two-year period, 1546 AGE stool samples from ten Brazilian states were analyzed by RT-qPCR to detect and quantify GI and GII noroviruses. Positive samples were genotyped by dual sequencing using the ORF1/2 junction region. Overall, we detected norovirus in 32.1% of samples, with a massive predominance of GII viruses (89.1%). We also observed a significant difference between the median viral load of norovirus GI (3.4×105 GC/g of stool) and GII (1.9×107 GC/g). The most affected age group was children aged between 6 and 24 m old, and norovirus infection was detected throughout the year without marked seasonality. Phylogenetic analysis of partial RdRp and VP1 regions identified six and 11 genotype combinations of GI and GII, respectively. GII.4 Sydney[P16] was by far the predominant genotype (47.6%), followed by GII.2[P16], GII.4 Sydney[P31], and GII.6[P7]. We detected, for the first time in Brazil, the intergenogroup recombinant genotype GIX.1[GII.P15]. Our study contributes to the knowledge of norovirus genotypes circulation at the national level, reinforcing the importance of molecular surveillance programs for future vaccine designs.

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First evaluation of coral recruitment in Madagascar

Western Indian Ocean Journal of Marine Science ◽

10.4314/wiojms.v20i1.5 ◽

2021 ◽

Vol 20 (1) ◽

pp. 47-62

Author(s):

Gildas G.B. Todinanahary ◽

Nomeniarivelo Hasintantely ◽

Igor Eeckhaut ◽

Thierry Lavitra

Keyword(s):

Larval Density ◽

Average Density ◽

Recruitment Rate ◽

Seasonal Distribution ◽

Coral Recruitment ◽

Significant Difference ◽

Southwest Region ◽

The Mean ◽

First Time ◽

Very High

The distribution of larvae and recruitment of scleractinians in the southwest region of Madagascar were evaluated for the first time between October 2013 and September 2014 at 3 sites. The presence of coral larvae (planulae) was monitored through weekly sampling using a plankton net and the recruitment rate evaluated by monthly sampling of the newly settled corals (<1 year stage) on recruitment tiles and by a monitoring of the recruitment of juveniles (1< Juveniles < 2 years) using the quadrat method. Planulae were present in the plankton for 9 months during the survey. The recorded mean annual density of planula varied from 0.43 ± 0.41 larvae m-3 to 3.23 ± 5.72 larvae m-3 depending on site, with a peak in larval density towards the end of November and the beginning of December. The variability in the occurrence of planula is very high and implied that the density observed in the year does not present a significant difference between the sites (pKW=0.33). The average density of total recruits was 620.13 ± 621.30 recruits m-2, 40.28 ± 50.97 recruits m-2 and 36.34 ± 33.82 recruits m-2, respectively at the sites of Nosy Tafara, Grande Vasque and Rose Garden. Seasonal distribution of coral recruitment was different between the sites. The mean annual density of newly settled recruits (< 1 month stage) was significantly higher at Nosy Tafara with 94.91±101.08 recruits m-2 compared to Grande Vasque and Rose Garden with 18.75±34.32 recruits m-2 and 11.57±18.47 recruits m-2 (pKW<0.001), respectively. The highest density of newly settled recruits was observed between October to December. Higher density of recruits was also observed in March at Nosy Tafara and in May at all three sites. Results of juvenile monitoring showed high rates (> 10 juveniles m-2) compared to other regions and the threshold, but it revealed high mortality among recruits. Coral recruitment in the southwest region of Madagascar was found to be high and could result in increased resilience of the coral reef assemblages.

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